I'm on a low carb diet and I would LOVE it if the myfitnesspal iOS app could show carbs remaining instead of calories remaining.
Perhaps the ability to show carbs remaining or calories remaining could be added to the app settings.
All of the data is already there, theoretically it should be possible to add a feature to highlight any collected data point.

If you go to the home page and hit the "daily" button (top middle) it'll show macro and nutrient levels for the day